code: def test_lpca_static():
      S0 = 100 * np.ones((20, 20, 20, 20), dtype="f8")
      S0ns = localpca(S0, sigma=np.ones((20, 20, 20), dtype=np.float64))
      assert_array_almost_equal(S0, S0ns)
  
imports: import warnings
  import numpy
  import scipy.special
  from numpy.testing import assert_, assert_equal, assert_raises, assert_array_almost_equal, assert_warns
  from dipy.denoise.localpca import dimensionality_problem_message, create_patch_radius_arr, compute_patch_size, compute_num_samples, compute_suggested_patch_radius, localpca, mppca, genpca, _pca_classifier
  from dipy.sims.voxel import multi_tensor
  from dipy.core.gradients import gradient_table, generate_bvecs
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 3 for calling a global function with example usage: test_lpca_static() without return types